Cutting device for woodworking tools



msm s Apr. 17, 1923.

S. MADSEN CUTTING DEVICE FOR WOODWOHKIILJG TOOLS Filed Dec. 11; 1922Patented Apr. 17, 1923.

FFWE.

SEEN MADSEN, OF CLINTON, IOWA.

CUTTING DEVICE FOR WOODWORKING TOOLS.

Application filed December 11, 1922.

To all whom it may concern Be it known that I, Snnn MADSEN, a cit1- zenof the United States, and a residentof Clinton, in the county of Clintonand State of Iowa have invented a certain new and useful utting Devicefor Woodworking Tools, of which the following is a spec1fication.

The object of my invention is to provide a simple, durable, compact andine rpensive cutting mechanism for wood working machinery having aseries of detachable b ts which may be easily and quickly placed 1nposition and when so placed willbe rigidly locked against movementrelative to the cutter head having radial clearance.

A further object is to provide a cutter head designed to carry a numberof detachable bits which are capable of being firmly locked into anumber of lateral positions relative to the path of travel of said bits.

A further object is to provide a cutter head having a series ofdetachable bits and locking devices having the same so arranged that anyadjustment of said locking devices may be made to adjust the bits andlock them in position in said head without changing the centrifugalbalance of the head.

A still further object is to provide in a cutting device for woodworking machinery having a head and detachable bits, improved means forsecuring the bits in position in such a manner that the cutting strainfrom the bits will not be carried directly to the actuating devices forlocking the bits in position.

A further object is to provide in a cutting device for wood workingmachinery, improved bits and means for locking the same in position inthe head whereby the minimum amount of steel may be employed for thesaid bits.

These and otherobjects will be apparent to those skilled in the art.

My invention consists in the construction arrangement and combination ofthe various parts of the device, whereby the objects contemplated areattained, as hereinafter more fully set forth, pointed out in my claims,and

illustrated in the accompanying drawings,

in which:

Serial No. 606,280.

Figure 1 is a side elevation of my improved cutting device.

F igure 2 is a vertical sectional view taken on the line 2-2 of Figure1.

Figure 3 is a sectional view taken on the l1ne 33 of Figure 1.

Figure 4 is a detail perspective view of one of the bits.

Figure 5 is a segmental isometrical View of the cutter head showing oneof the bit re taming notches.

My improved cutting device comprises a head member 10 which is formedpreferably cylindrical and provided with an opening 11 at its center.This opening is for the purpose of securing the said head to the cutterarbor in the usual manner. The head is preferably formed of a solidpiece of tool steel or brass of any desired width and diameter.

In the periphery of the head 10 I have provided a series of notches 12which are formed by first drilling openings 13 and 14; with the ordinarypress drill. The openings 13 are then reamed, the said opening being ofconsiderably larger diameter than the opening 1%, the opening 14: beingdrilled at a' shorter radius from the center of the head than theopening 13, substantially as shown in Figure 1.

After the holes 13 and 1 1 have been drilled, the head is placed in amilling machine and an annular slot 15 is cut to communicate with boththe openings 13 and 1 1. The angle of the said slot is preferably atabout thirty degrees from the radial line. One side of the slot 15,which I shall term the back side, is substantially in line with the backside of the opening 14:. The bottom of said slot is substantially inline with the inner side of said opening. The front side of the slot,however, is substantially in line with the center of the opening 13 sothat a recess may be formed in the said notch. The back and face of thesaid slot are parallel with each other, and the bottom of said slot isparallel with the opening 11. The notches 12 are all of the same sizeand the member 10 is perfectly balanced.

Mounted within each of the notches 12 is a bit member 16 which has itsbase of a width substantially equal to the width of the member 10, andthe thickness of the said bit is equal to the width of the slot 15. Theinner end of the bit is shaped to coincide with the bottom of said slot.

Opposite the recess 15 l have provided a transversely extending\l-shaped notch 17 in the bit. The outer face of the notch 17 isparallel with the inner end of the member 16, while the opposite face ofthe notch 17 is substantially parallel with the radial line of thecutter head. This face, however, is provided with two portions 18 whichare beveledrearwardly and outwardly from the center of t'liesaidface, asclearl shown in Figure 4E. v Q

fFor locking the member 16 in position, I have provided two cylindricallocking members 19, each of which isprovided with a flattened andinclined face, the said faces b'eing'designed to coact with the portions18 of the cutter member. These locking devices are arranged in each endof the recess 13, asclearly shown in Figure 3, with their central endsspaced apart a slight distance. as'crew 21 extends centrally through oneofthe members 19 and is screwed into the cipposite member. The head ofthe said screw is countersunk, and the said screw of alength sligthlyless than the width ofthe cutter head so that when the members 19a'reassembled, the said members will rest within tlie face of the head 10.

By the arrangement just described, it will be clearly seen that if thescrew 21 is rotated, the" two members 19 may be drawn toward each otherwhile their inclined faces will engage the portions 18 of the cutter,and tlieircylindrical portion will rest in the recess '13. This movementtoward each other iizill cause the member 16 to be firmly gripped withinthe notch 12 and held against movement in any direction. The outer endoflthe member 16 may be provided with any convenient cutting portion 22.

By this arrangement, it will be seen that the cutters may be sharpenedby grinding the front face of the member 16, the said face to groundparallel to the back face of'the said member at the proper point without'weakening the member 16. By

. grinding the forward face of the member 1,6, itw ill be seen that thecontour of the cntting member 22 will not be altered, nor the tool,materially shortened.

By niolunting the member 16 in the notch 12 as justdescribed with itsinner face adj'acentto the bottom of said notch and its back faceadjacent to the back face of the said notch, it will be seen that theangle of all the cutters will be exactly the same. Their radiallengthwill also be the same without any delicate adjustment.

It willalso be seen that the member 16 must be so adjusted laterallyrelative to the travel of the cutter portion in order to make a tongueand groove portion of the said cutters in line with each other. This iseasily done due to the fact that the said bits are free to move in saidlateral direction, and when properly placed, the screw 21 of the lockingmechanism may be operated which will cause the members 19 to firmly lockthe said member in position.

In this connection, it will be noted that the movement of the members 19in opposite directions will eliminate any tendency whatever to move themember 16 after it has been set and while it is being locked.

it is sometimes desirable that, the cutters beplaced out of truealinement with each other so that the grooves and tenons may be of aslight difference in width. This may also be quickly and accuratelyaccomplished, which is not possible in devices heretofore employed whichhave a series f grooves'and tongues for lining the cutters in theirlateral direction.

In regard to the wedge members 19, it will be seen that the inclinedfaces will always be in alinement with the faces 18due to the fact thatthe members 19 are cylindrical and rest in cylindrical recesses so thata slight pivotal movement is permittech'due to "the irregularity in theangle of the faces 18.

it will also be noted that equal pressure will be applied to each of thefaces 18 of the cutter so as to always firmly hold thesaid" cutter inposition against any rocking movement, even though the machine work ofthe faces 18 and the inclined portion 20 shall not be absolutelyaccurate. i'inother advantage in the construction of my device lies inthe fact that the \l shaped notch 17 is so arranged in the front face ofthe member 16 that a sort of dovetailed joint is employed to prevent itfrom being thrown outwardly due to cei'itrifugal force.

It will also be noted that when the strain is applied to the cutting endofthe bi t,the outer end of the bit will have a tendency to movebackward while the inner end will have a tendency to move forwardly,said forward movement resting directly againstthe members 19, andmaterially none of the strain being applied to the screw 21. Thisprovides a very rigid lock which may be easily and quickly adjustedbythe use of an ordinary screw driver, and'whenl'ocked will not workloose dueto the severe ten dency toward vibration of the bit members asthey engage the mateljial to becut It will also be seenthat anymovementof the members 19 which is necessary in order to'clamp the bits 16 intoposition will not in any way change the centrilical balance of the headdue tothefact thatthe said movement is in a line parallel with the axisof the rotary member. I have-found that any movement of a lockingdevicewhich moves radially in order to secure the bits in position, willchange the balance of the head.

It will also be noted on account of the members 19 moving in oppositedirections that the power necessary to move the said members isconsiderably less than would be necessary if one of the members werestationary, and the locking is also done by the movable member.

The feature of providing a circular recess at each corner of the slot 15also serves to strengthen the head, inasmuch as the circular cornerswill not crystallize and crack as will sharp angular corners. This alsosimplifies the construction of said notches 12 due to the fact that thewedge device is very effective, thereby permitting the use of a veryshallow notch in order to rigidly hold the bit in position. This reducesthe diameter of the member 10 and also permits a larger number ofcutters to be used on the head of a given diameter, due to the fact thatthe said cutter or bits may be placed comparatively close to each otherwithout materially weakening the said head.

It will also be noted that both faces of the head are smooth and freefrom projections which might catch on the workmens clothes or mar thematerial upon which the cutter is operated. The centrifugal action ofthe bit has a tendency to tighten it rather than loosen it.

Thus it will be seen that I have provided a tool for wood workingmachinery comprising a head member and detachable bits which may beeasily, quickly and accurately adjusted, and when once adjusted will notwork loose, and so designed as to employ the minimum amount of highpriced material such as bits are usually constructed of.

I claim as my invention:

1. In a device of the class described, a cutter head adapted to rotateand provided with a series of slots parallel with its axis of rotation,a bit for each of said slots, each provided with oppositely arrangedinclined faces, a rotatively mounted wedge device for each of saidinclined faces, and means for drawing said wedge devices toward eachother and longitudinally with the axis of said head member to lock thesaid bits in position, said bits being capable of adjustment axially.

2. In a device of the class described, a cutter head adapted to rotateand provided with a series of slots parallel with its axis of rotation,the forward face of each of said slots being provided with asemi-circular groove, a bit for each of said slots, the forward face ofeach of said bits being provided with a V-shaped groove, one face ofsaid V-shaped grooves being provided with oppositely inclined faces, apair of cylindrical wedge members each being provided with an inclinedflattened face to rest in said semi-circular groove and to coact withcorresponding inclined faces of said V- shaped grooves, a screw fordrawing said wedge devices toward each other, the said wedge devices andsaid bit being capable of axial adjustment in said slots.

3. In a device of the class described, a cutter head adapted to rotateand provided with a series of slots parallel with its axis of rotation,said slots being arranged tangentially with the axial center of saidcutter, each having their forward faces provided with a semi-circulargroove, a bit for each of said slots, that portion of the forward faceof each of said bits which rests opposite the semi-circular groove whenthe bit is in position in said slots is provided with a V-shaped slotrunning parallel with said semi-circular grooves, one of the faces ofsaid V-shaped slot being substantially radial with the center of thecutter head, and the opposite face of said V-shaped slot beingsubstantially at right angles to the said radial face, the radial face.being provided with oppositely inclined faces, a pair of cylindricalwedge members for said semicircular groove and said V-shaped groove,said wedge members each being provided with an inclined flattened faceto correspond with the inclined faces of said V-shaped groove, a screwcentrally arranged with said cylindrical wedges for drawing them together.

Des Moines, Iowa, September 15, 1922.

SER-N NLADSEN

